Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 934 insertions, 0 deletions

diff --git a/drivers/net/wireless/intel/iwlegacy/4965-calib.c b/drivers/net/wireless/intel/iwlegacy/4965-calib.c
new file mode 100644
index 000000000..2f97cbd42
--- /dev/null
+++ b/drivers/net/wireless/intel/iwlegacy/4965-calib.c
@@ -0,0 +1,934 @@
+/******************************************************************************
+ *
+ * This file is provided under a dual BSD/GPLv2 license.  When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * GPL LICENSE SUMMARY
+ *
+ * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110,
+ * USA
+ *
+ * The full GNU General Public License is included in this distribution
+ * in the file called LICENSE.GPL.
+ *
+ * Contact Information:
+ *  Intel Linux Wireless <ilw@linux.intel.com>
+ * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
+ *
+ * BSD LICENSE
+ *
+ * Copyright(c) 2005 - 2011 Intel Corporation. All rights reserved.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *  * Neither the name Intel Corporation nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *****************************************************************************/
+
+#include <linux/slab.h>
+#include <net/mac80211.h>
+
+#include "common.h"
+#include "4965.h"
+
+/*****************************************************************************
+ * INIT calibrations framework
+ *****************************************************************************/
+
+struct stats_general_data {
+	u32 beacon_silence_rssi_a;
+	u32 beacon_silence_rssi_b;
+	u32 beacon_silence_rssi_c;
+	u32 beacon_energy_a;
+	u32 beacon_energy_b;
+	u32 beacon_energy_c;
+};
+
+/*****************************************************************************
+ * RUNTIME calibrations framework
+ *****************************************************************************/
+
+/* "false alarms" are signals that our DSP tries to lock onto,
+ *   but then determines that they are either noise, or transmissions
+ *   from a distant wireless network (also "noise", really) that get
+ *   "stepped on" by stronger transmissions within our own network.
+ * This algorithm attempts to set a sensitivity level that is high
+ *   enough to receive all of our own network traffic, but not so
+ *   high that our DSP gets too busy trying to lock onto non-network
+ *   activity/noise. */
+static int
+il4965_sens_energy_cck(struct il_priv *il, u32 norm_fa, u32 rx_enable_time,
+		       struct stats_general_data *rx_info)
+{
+	u32 max_nrg_cck = 0;
+	int i = 0;
+	u8 max_silence_rssi = 0;
+	u32 silence_ref = 0;
+	u8 silence_rssi_a = 0;
+	u8 silence_rssi_b = 0;
+	u8 silence_rssi_c = 0;
+	u32 val;
+
+	/* "false_alarms" values below are cross-multiplications to assess the
+	 *   numbers of false alarms within the measured period of actual Rx
+	 *   (Rx is off when we're txing), vs the min/max expected false alarms
+	 *   (some should be expected if rx is sensitive enough) in a
+	 *   hypothetical listening period of 200 time units (TU), 204.8 msec:
+	 *
+	 * MIN_FA/fixed-time < false_alarms/actual-rx-time < MAX_FA/beacon-time
+	 *
+	 * */
+	u32 false_alarms = norm_fa * 200 * 1024;
+	u32 max_false_alarms = MAX_FA_CCK * rx_enable_time;
+	u32 min_false_alarms = MIN_FA_CCK * rx_enable_time;
+	struct il_sensitivity_data *data = NULL;
+	const struct il_sensitivity_ranges *ranges = il->hw_params.sens;
+
+	data = &(il->sensitivity_data);
+
+	data->nrg_auto_corr_silence_diff = 0;
+
+	/* Find max silence rssi among all 3 receivers.
+	 * This is background noise, which may include transmissions from other
+	 *    networks, measured during silence before our network's beacon */
+	silence_rssi_a =
+	    (u8) ((rx_info->beacon_silence_rssi_a & ALL_BAND_FILTER) >> 8);
+	silence_rssi_b =
+	    (u8) ((rx_info->beacon_silence_rssi_b & ALL_BAND_FILTER) >> 8);
+	silence_rssi_c =
+	    (u8) ((rx_info->beacon_silence_rssi_c & ALL_BAND_FILTER) >> 8);
+
+	val = max(silence_rssi_b, silence_rssi_c);
+	max_silence_rssi = max(silence_rssi_a, (u8) val);
+
+	/* Store silence rssi in 20-beacon history table */
+	data->nrg_silence_rssi[data->nrg_silence_idx] = max_silence_rssi;
+	data->nrg_silence_idx++;
+	if (data->nrg_silence_idx >= NRG_NUM_PREV_STAT_L)
+		data->nrg_silence_idx = 0;
+
+	/* Find max silence rssi across 20 beacon history */
+	for (i = 0; i < NRG_NUM_PREV_STAT_L; i++) {
+		val = data->nrg_silence_rssi[i];
+		silence_ref = max(silence_ref, val);
+	}
+	D_CALIB("silence a %u, b %u, c %u, 20-bcn max %u\n", silence_rssi_a,
+		silence_rssi_b, silence_rssi_c, silence_ref);
+
+	/* Find max rx energy (min value!) among all 3 receivers,
+	 *   measured during beacon frame.
+	 * Save it in 10-beacon history table. */
+	i = data->nrg_energy_idx;
+	val = min(rx_info->beacon_energy_b, rx_info->beacon_energy_c);
+	data->nrg_value[i] = min(rx_info->beacon_energy_a, val);
+
+	data->nrg_energy_idx++;
+	if (data->nrg_energy_idx >= 10)
+		data->nrg_energy_idx = 0;
+
+	/* Find min rx energy (max value) across 10 beacon history.
+	 * This is the minimum signal level that we want to receive well.
+	 * Add backoff (margin so we don't miss slightly lower energy frames).
+	 * This establishes an upper bound (min value) for energy threshold. */
+	max_nrg_cck = data->nrg_value[0];
+	for (i = 1; i < 10; i++)
+		max_nrg_cck = (u32) max(max_nrg_cck, (data->nrg_value[i]));
+	max_nrg_cck += 6;
+
+	D_CALIB("rx energy a %u, b %u, c %u, 10-bcn max/min %u\n",
+		rx_info->beacon_energy_a, rx_info->beacon_energy_b,
+		rx_info->beacon_energy_c, max_nrg_cck - 6);
+
+	/* Count number of consecutive beacons with fewer-than-desired
+	 *   false alarms. */
+	if (false_alarms < min_false_alarms)
+		data->num_in_cck_no_fa++;
+	else
+		data->num_in_cck_no_fa = 0;
+	D_CALIB("consecutive bcns with few false alarms = %u\n",
+		data->num_in_cck_no_fa);
+
+	/* If we got too many false alarms this time, reduce sensitivity */
+	if (false_alarms > max_false_alarms &&
+	    data->auto_corr_cck > AUTO_CORR_MAX_TH_CCK) {
+		D_CALIB("norm FA %u > max FA %u\n", false_alarms,
+			max_false_alarms);
+		D_CALIB("... reducing sensitivity\n");
+		data->nrg_curr_state = IL_FA_TOO_MANY;
+		/* Store for "fewer than desired" on later beacon */
+		data->nrg_silence_ref = silence_ref;
+
+		/* increase energy threshold (reduce nrg value)
+		 *   to decrease sensitivity */
+		data->nrg_th_cck = data->nrg_th_cck - NRG_STEP_CCK;
+		/* Else if we got fewer than desired, increase sensitivity */
+	} else if (false_alarms < min_false_alarms) {
+		data->nrg_curr_state = IL_FA_TOO_FEW;
+
+		/* Compare silence level with silence level for most recent
+		 *   healthy number or too many false alarms */
+		data->nrg_auto_corr_silence_diff =
+		    (s32) data->nrg_silence_ref - (s32) silence_ref;
+
+		D_CALIB("norm FA %u < min FA %u, silence diff %d\n",
+			false_alarms, min_false_alarms,
+			data->nrg_auto_corr_silence_diff);
+
+		/* Increase value to increase sensitivity, but only if:
+		 * 1a) previous beacon did *not* have *too many* false alarms
+		 * 1b) AND there's a significant difference in Rx levels
+		 *      from a previous beacon with too many, or healthy # FAs
+		 * OR 2) We've seen a lot of beacons (100) with too few
+		 *       false alarms */
+		if (data->nrg_prev_state != IL_FA_TOO_MANY &&
+		    (data->nrg_auto_corr_silence_diff > NRG_DIFF ||
+		     data->num_in_cck_no_fa > MAX_NUMBER_CCK_NO_FA)) {
+
+			D_CALIB("... increasing sensitivity\n");
+			/* Increase nrg value to increase sensitivity */
+			val = data->nrg_th_cck + NRG_STEP_CCK;
+			data->nrg_th_cck = min((u32) ranges->min_nrg_cck, val);
+		} else {
+			D_CALIB("... but not changing sensitivity\n");
+		}
+
+		/* Else we got a healthy number of false alarms, keep status quo */
+	} else {
+		D_CALIB(" FA in safe zone\n");
+		data->nrg_curr_state = IL_FA_GOOD_RANGE;
+
+		/* Store for use in "fewer than desired" with later beacon */
+		data->nrg_silence_ref = silence_ref;
+
+		/* If previous beacon had too many false alarms,
+		 *   give it some extra margin by reducing sensitivity again
+		 *   (but don't go below measured energy of desired Rx) */
+		if (IL_FA_TOO_MANY == data->nrg_prev_state) {
+			D_CALIB("... increasing margin\n");
+			if (data->nrg_th_cck > (max_nrg_cck + NRG_MARGIN))
+				data->nrg_th_cck -= NRG_MARGIN;
+			else
+				data->nrg_th_cck = max_nrg_cck;
+		}
+	}
+
+	/* Make sure the energy threshold does not go above the measured
+	 * energy of the desired Rx signals (reduced by backoff margin),
+	 * or else we might start missing Rx frames.
+	 * Lower value is higher energy, so we use max()!
+	 */
+	data->nrg_th_cck = max(max_nrg_cck, data->nrg_th_cck);
+	D_CALIB("new nrg_th_cck %u\n", data->nrg_th_cck);
+
+	data->nrg_prev_state = data->nrg_curr_state;
+
+	/* Auto-correlation CCK algorithm */
+	if (false_alarms > min_false_alarms) {
+
+		/* increase auto_corr values to decrease sensitivity
+		 * so the DSP won't be disturbed by the noise
+		 */
+		if (data->auto_corr_cck < AUTO_CORR_MAX_TH_CCK)
+			data->auto_corr_cck = AUTO_CORR_MAX_TH_CCK + 1;
+		else {
+			val = data->auto_corr_cck + AUTO_CORR_STEP_CCK;
+			data->auto_corr_cck =
+			    min((u32) ranges->auto_corr_max_cck, val);
+		}
+		val = data->auto_corr_cck_mrc + AUTO_CORR_STEP_CCK;
+		data->auto_corr_cck_mrc =
+		    min((u32) ranges->auto_corr_max_cck_mrc, val);
+	} else if (false_alarms < min_false_alarms &&
+		   (data->nrg_auto_corr_silence_diff > NRG_DIFF ||
+		    data->num_in_cck_no_fa > MAX_NUMBER_CCK_NO_FA)) {
+
+		/* Decrease auto_corr values to increase sensitivity */
+		val = data->auto_corr_cck - AUTO_CORR_STEP_CCK;
+		data->auto_corr_cck = max((u32) ranges->auto_corr_min_cck, val);
+		val = data->auto_corr_cck_mrc - AUTO_CORR_STEP_CCK;
+		data->auto_corr_cck_mrc =
+		    max((u32) ranges->auto_corr_min_cck_mrc, val);
+	}
+
+	return 0;
+}
+
+static int
+il4965_sens_auto_corr_ofdm(struct il_priv *il, u32 norm_fa, u32 rx_enable_time)
+{
+	u32 val;
+	u32 false_alarms = norm_fa * 200 * 1024;
+	u32 max_false_alarms = MAX_FA_OFDM * rx_enable_time;
+	u32 min_false_alarms = MIN_FA_OFDM * rx_enable_time;
+	struct il_sensitivity_data *data = NULL;
+	const struct il_sensitivity_ranges *ranges = il->hw_params.sens;
+
+	data = &(il->sensitivity_data);
+
+	/* If we got too many false alarms this time, reduce sensitivity */
+	if (false_alarms > max_false_alarms) {
+
+		D_CALIB("norm FA %u > max FA %u)\n", false_alarms,
+			max_false_alarms);
+
+		val = data->auto_corr_ofdm + AUTO_CORR_STEP_OFDM;
+		data->auto_corr_ofdm =
+		    min((u32) ranges->auto_corr_max_ofdm, val);
+
+		val = data->auto_corr_ofdm_mrc + AUTO_CORR_STEP_OFDM;
+		data->auto_corr_ofdm_mrc =
+		    min((u32) ranges->auto_corr_max_ofdm_mrc, val);
+
+		val = data->auto_corr_ofdm_x1 + AUTO_CORR_STEP_OFDM;
+		data->auto_corr_ofdm_x1 =
+		    min((u32) ranges->auto_corr_max_ofdm_x1, val);
+
+		val = data->auto_corr_ofdm_mrc_x1 + AUTO_CORR_STEP_OFDM;
+		data->auto_corr_ofdm_mrc_x1 =
+		    min((u32) ranges->auto_corr_max_ofdm_mrc_x1, val);
+	}
+
+	/* Else if we got fewer than desired, increase sensitivity */
+	else if (false_alarms < min_false_alarms) {
+
+		D_CALIB("norm FA %u < min FA %u\n", false_alarms,
+			min_false_alarms);
+
+		val = data->auto_corr_ofdm - AUTO_CORR_STEP_OFDM;
+		data->auto_corr_ofdm =
+		    max((u32) ranges->auto_corr_min_ofdm, val);
+
+		val = data->auto_corr_ofdm_mrc - AUTO_CORR_STEP_OFDM;
+		data->auto_corr_ofdm_mrc =
+		    max((u32) ranges->auto_corr_min_ofdm_mrc, val);
+
+		val = data->auto_corr_ofdm_x1 - AUTO_CORR_STEP_OFDM;
+		data->auto_corr_ofdm_x1 =
+		    max((u32) ranges->auto_corr_min_ofdm_x1, val);
+
+		val = data->auto_corr_ofdm_mrc_x1 - AUTO_CORR_STEP_OFDM;
+		data->auto_corr_ofdm_mrc_x1 =
+		    max((u32) ranges->auto_corr_min_ofdm_mrc_x1, val);
+	} else {
+		D_CALIB("min FA %u < norm FA %u < max FA %u OK\n",
+			min_false_alarms, false_alarms, max_false_alarms);
+	}
+	return 0;
+}
+
+static void
+il4965_prepare_legacy_sensitivity_tbl(struct il_priv *il,
+				      struct il_sensitivity_data *data,
+				      __le16 *tbl)
+{
+	tbl[HD_AUTO_CORR32_X4_TH_ADD_MIN_IDX] =
+	    cpu_to_le16((u16) data->auto_corr_ofdm);
+	tbl[HD_AUTO_CORR32_X4_TH_ADD_MIN_MRC_IDX] =
+	    cpu_to_le16((u16) data->auto_corr_ofdm_mrc);
+	tbl[HD_AUTO_CORR32_X1_TH_ADD_MIN_IDX] =
+	    cpu_to_le16((u16) data->auto_corr_ofdm_x1);
+	tbl[HD_AUTO_CORR32_X1_TH_ADD_MIN_MRC_IDX] =
+	    cpu_to_le16((u16) data->auto_corr_ofdm_mrc_x1);
+
+	tbl[HD_AUTO_CORR40_X4_TH_ADD_MIN_IDX] =
+	    cpu_to_le16((u16) data->auto_corr_cck);
+	tbl[HD_AUTO_CORR40_X4_TH_ADD_MIN_MRC_IDX] =
+	    cpu_to_le16((u16) data->auto_corr_cck_mrc);
+
+	tbl[HD_MIN_ENERGY_CCK_DET_IDX] = cpu_to_le16((u16) data->nrg_th_cck);
+	tbl[HD_MIN_ENERGY_OFDM_DET_IDX] = cpu_to_le16((u16) data->nrg_th_ofdm);
+
+	tbl[HD_BARKER_CORR_TH_ADD_MIN_IDX] =
+	    cpu_to_le16(data->barker_corr_th_min);
+	tbl[HD_BARKER_CORR_TH_ADD_MIN_MRC_IDX] =
+	    cpu_to_le16(data->barker_corr_th_min_mrc);
+	tbl[HD_OFDM_ENERGY_TH_IN_IDX] = cpu_to_le16(data->nrg_th_cca);
+
+	D_CALIB("ofdm: ac %u mrc %u x1 %u mrc_x1 %u thresh %u\n",
+		data->auto_corr_ofdm, data->auto_corr_ofdm_mrc,
+		data->auto_corr_ofdm_x1, data->auto_corr_ofdm_mrc_x1,
+		data->nrg_th_ofdm);
+
+	D_CALIB("cck: ac %u mrc %u thresh %u\n", data->auto_corr_cck,
+		data->auto_corr_cck_mrc, data->nrg_th_cck);
+}
+
+/* Prepare a C_SENSITIVITY, send to uCode if values have changed */
+static int
+il4965_sensitivity_write(struct il_priv *il)
+{
+	struct il_sensitivity_cmd cmd;
+	struct il_sensitivity_data *data = NULL;
+	struct il_host_cmd cmd_out = {
+		.id = C_SENSITIVITY,
+		.len = sizeof(struct il_sensitivity_cmd),
+		.flags = CMD_ASYNC,
+		.data = &cmd,
+	};
+
+	data = &(il->sensitivity_data);
+
+	memset(&cmd, 0, sizeof(cmd));
+
+	il4965_prepare_legacy_sensitivity_tbl(il, data, &cmd.table[0]);
+
+	/* Update uCode's "work" table, and copy it to DSP */
+	cmd.control = C_SENSITIVITY_CONTROL_WORK_TBL;
+
+	/* Don't send command to uCode if nothing has changed */
+	if (!memcmp
+	    (&cmd.table[0], &(il->sensitivity_tbl[0]),
+	     sizeof(u16) * HD_TBL_SIZE)) {
+		D_CALIB("No change in C_SENSITIVITY\n");
+		return 0;
+	}
+
+	/* Copy table for comparison next time */
+	memcpy(&(il->sensitivity_tbl[0]), &(cmd.table[0]),
+	       sizeof(u16) * HD_TBL_SIZE);
+
+	return il_send_cmd(il, &cmd_out);
+}
+
+void
+il4965_init_sensitivity(struct il_priv *il)
+{
+	int ret = 0;
+	int i;
+	struct il_sensitivity_data *data = NULL;
+	const struct il_sensitivity_ranges *ranges = il->hw_params.sens;
+
+	if (il->disable_sens_cal)
+		return;
+
+	D_CALIB("Start il4965_init_sensitivity\n");
+
+	/* Clear driver's sensitivity algo data */
+	data = &(il->sensitivity_data);
+
+	if (ranges == NULL)
+		return;
+
+	memset(data, 0, sizeof(struct il_sensitivity_data));
+
+	data->num_in_cck_no_fa = 0;
+	data->nrg_curr_state = IL_FA_TOO_MANY;
+	data->nrg_prev_state = IL_FA_TOO_MANY;
+	data->nrg_silence_ref = 0;
+	data->nrg_silence_idx = 0;
+	data->nrg_energy_idx = 0;
+
+	for (i = 0; i < 10; i++)
+		data->nrg_value[i] = 0;
+
+	for (i = 0; i < NRG_NUM_PREV_STAT_L; i++)
+		data->nrg_silence_rssi[i] = 0;
+
+	data->auto_corr_ofdm = ranges->auto_corr_min_ofdm;
+	data->auto_corr_ofdm_mrc = ranges->auto_corr_min_ofdm_mrc;
+	data->auto_corr_ofdm_x1 = ranges->auto_corr_min_ofdm_x1;
+	data->auto_corr_ofdm_mrc_x1 = ranges->auto_corr_min_ofdm_mrc_x1;
+	data->auto_corr_cck = AUTO_CORR_CCK_MIN_VAL_DEF;
+	data->auto_corr_cck_mrc = ranges->auto_corr_min_cck_mrc;
+	data->nrg_th_cck = ranges->nrg_th_cck;
+	data->nrg_th_ofdm = ranges->nrg_th_ofdm;
+	data->barker_corr_th_min = ranges->barker_corr_th_min;
+	data->barker_corr_th_min_mrc = ranges->barker_corr_th_min_mrc;
+	data->nrg_th_cca = ranges->nrg_th_cca;
+
+	data->last_bad_plcp_cnt_ofdm = 0;
+	data->last_fa_cnt_ofdm = 0;
+	data->last_bad_plcp_cnt_cck = 0;
+	data->last_fa_cnt_cck = 0;
+
+	ret |= il4965_sensitivity_write(il);
+	D_CALIB("<<return 0x%X\n", ret);
+}
+
+void
+il4965_sensitivity_calibration(struct il_priv *il, void *resp)
+{
+	u32 rx_enable_time;
+	u32 fa_cck;
+	u32 fa_ofdm;
+	u32 bad_plcp_cck;
+	u32 bad_plcp_ofdm;
+	u32 norm_fa_ofdm;
+	u32 norm_fa_cck;
+	struct il_sensitivity_data *data = NULL;
+	struct stats_rx_non_phy *rx_info;
+	struct stats_rx_phy *ofdm, *cck;
+	unsigned long flags;
+	struct stats_general_data statis;
+
+	if (il->disable_sens_cal)
+		return;
+
+	data = &(il->sensitivity_data);
+
+	if (!il_is_any_associated(il)) {
+		D_CALIB("<< - not associated\n");
+		return;
+	}
+
+	spin_lock_irqsave(&il->lock, flags);
+
+	rx_info = &(((struct il_notif_stats *)resp)->rx.general);
+	ofdm = &(((struct il_notif_stats *)resp)->rx.ofdm);
+	cck = &(((struct il_notif_stats *)resp)->rx.cck);
+
+	if (rx_info->interference_data_flag != INTERFERENCE_DATA_AVAILABLE) {
+		D_CALIB("<< invalid data.\n");
+		spin_unlock_irqrestore(&il->lock, flags);
+		return;
+	}
+
+	/* Extract Statistics: */
+	rx_enable_time = le32_to_cpu(rx_info->channel_load);
+	fa_cck = le32_to_cpu(cck->false_alarm_cnt);
+	fa_ofdm = le32_to_cpu(ofdm->false_alarm_cnt);
+	bad_plcp_cck = le32_to_cpu(cck->plcp_err);
+	bad_plcp_ofdm = le32_to_cpu(ofdm->plcp_err);
+
+	statis.beacon_silence_rssi_a =
+	    le32_to_cpu(rx_info->beacon_silence_rssi_a);
+	statis.beacon_silence_rssi_b =
+	    le32_to_cpu(rx_info->beacon_silence_rssi_b);
+	statis.beacon_silence_rssi_c =
+	    le32_to_cpu(rx_info->beacon_silence_rssi_c);
+	statis.beacon_energy_a = le32_to_cpu(rx_info->beacon_energy_a);
+	statis.beacon_energy_b = le32_to_cpu(rx_info->beacon_energy_b);
+	statis.beacon_energy_c = le32_to_cpu(rx_info->beacon_energy_c);
+
+	spin_unlock_irqrestore(&il->lock, flags);
+
+	D_CALIB("rx_enable_time = %u usecs\n", rx_enable_time);
+
+	if (!rx_enable_time) {
+		D_CALIB("<< RX Enable Time == 0!\n");
+		return;
+	}
+
+	/* These stats increase monotonically, and do not reset
+	 *   at each beacon.  Calculate difference from last value, or just
+	 *   use the new stats value if it has reset or wrapped around. */
+	if (data->last_bad_plcp_cnt_cck > bad_plcp_cck)
+		data->last_bad_plcp_cnt_cck = bad_plcp_cck;
+	else {
+		bad_plcp_cck -= data->last_bad_plcp_cnt_cck;
+		data->last_bad_plcp_cnt_cck += bad_plcp_cck;
+	}
+
+	if (data->last_bad_plcp_cnt_ofdm > bad_plcp_ofdm)
+		data->last_bad_plcp_cnt_ofdm = bad_plcp_ofdm;
+	else {
+		bad_plcp_ofdm -= data->last_bad_plcp_cnt_ofdm;
+		data->last_bad_plcp_cnt_ofdm += bad_plcp_ofdm;
+	}
+
+	if (data->last_fa_cnt_ofdm > fa_ofdm)
+		data->last_fa_cnt_ofdm = fa_ofdm;
+	else {
+		fa_ofdm -= data->last_fa_cnt_ofdm;
+		data->last_fa_cnt_ofdm += fa_ofdm;
+	}
+
+	if (data->last_fa_cnt_cck > fa_cck)
+		data->last_fa_cnt_cck = fa_cck;
+	else {
+		fa_cck -= data->last_fa_cnt_cck;
+		data->last_fa_cnt_cck += fa_cck;
+	}
+
+	/* Total aborted signal locks */
+	norm_fa_ofdm = fa_ofdm + bad_plcp_ofdm;
+	norm_fa_cck = fa_cck + bad_plcp_cck;
+
+	D_CALIB("cck: fa %u badp %u  ofdm: fa %u badp %u\n", fa_cck,
+		bad_plcp_cck, fa_ofdm, bad_plcp_ofdm);
+
+	il4965_sens_auto_corr_ofdm(il, norm_fa_ofdm, rx_enable_time);
+	il4965_sens_energy_cck(il, norm_fa_cck, rx_enable_time, &statis);
+
+	il4965_sensitivity_write(il);
+}
+
+static inline u8
+il4965_find_first_chain(u8 mask)
+{
+	if (mask & ANT_A)
+		return CHAIN_A;
+	if (mask & ANT_B)
+		return CHAIN_B;
+	return CHAIN_C;
+}
+
+/*
+ * Run disconnected antenna algorithm to find out which antennas are
+ * disconnected.
+ */
+static void
+il4965_find_disconn_antenna(struct il_priv *il, u32 * average_sig,
+			    struct il_chain_noise_data *data)
+{
+	u32 active_chains = 0;
+	u32 max_average_sig;
+	u16 max_average_sig_antenna_i;
+	u8 num_tx_chains;
+	u8 first_chain;
+	u16 i = 0;
+
+	average_sig[0] =
+	    data->chain_signal_a /
+	    il->cfg->chain_noise_num_beacons;
+	average_sig[1] =
+	    data->chain_signal_b /
+	    il->cfg->chain_noise_num_beacons;
+	average_sig[2] =
+	    data->chain_signal_c /
+	    il->cfg->chain_noise_num_beacons;
+
+	if (average_sig[0] >= average_sig[1]) {
+		max_average_sig = average_sig[0];
+		max_average_sig_antenna_i = 0;
+		active_chains = (1 << max_average_sig_antenna_i);
+	} else {
+		max_average_sig = average_sig[1];
+		max_average_sig_antenna_i = 1;
+		active_chains = (1 << max_average_sig_antenna_i);
+	}
+
+	if (average_sig[2] >= max_average_sig) {
+		max_average_sig = average_sig[2];
+		max_average_sig_antenna_i = 2;
+		active_chains = (1 << max_average_sig_antenna_i);
+	}
+
+	D_CALIB("average_sig: a %d b %d c %d\n", average_sig[0], average_sig[1],
+		average_sig[2]);
+	D_CALIB("max_average_sig = %d, antenna %d\n", max_average_sig,
+		max_average_sig_antenna_i);
+
+	/* Compare signal strengths for all 3 receivers. */
+	for (i = 0; i < NUM_RX_CHAINS; i++) {
+		if (i != max_average_sig_antenna_i) {
+			s32 rssi_delta = (max_average_sig - average_sig[i]);
+
+			/* If signal is very weak, compared with
+			 * strongest, mark it as disconnected. */
+			if (rssi_delta > MAXIMUM_ALLOWED_PATHLOSS)
+				data->disconn_array[i] = 1;
+			else
+				active_chains |= (1 << i);
+			D_CALIB("i = %d  rssiDelta = %d  "
+				"disconn_array[i] = %d\n", i, rssi_delta,
+				data->disconn_array[i]);
+		}
+	}
+
+	/*
+	 * The above algorithm sometimes fails when the ucode
+	 * reports 0 for all chains. It's not clear why that
+	 * happens to start with, but it is then causing trouble
+	 * because this can make us enable more chains than the
+	 * hardware really has.
+	 *
+	 * To be safe, simply mask out any chains that we know
+	 * are not on the device.
+	 */
+	active_chains &= il->hw_params.valid_rx_ant;
+
+	num_tx_chains = 0;
+	for (i = 0; i < NUM_RX_CHAINS; i++) {
+		/* loops on all the bits of
+		 * il->hw_setting.valid_tx_ant */
+		u8 ant_msk = (1 << i);
+		if (!(il->hw_params.valid_tx_ant & ant_msk))
+			continue;
+
+		num_tx_chains++;
+		if (data->disconn_array[i] == 0)
+			/* there is a Tx antenna connected */
+			break;
+		if (num_tx_chains == il->hw_params.tx_chains_num &&
+		    data->disconn_array[i]) {
+			/*
+			 * If all chains are disconnected
+			 * connect the first valid tx chain
+			 */
+			first_chain =
+			    il4965_find_first_chain(il->cfg->valid_tx_ant);
+			data->disconn_array[first_chain] = 0;
+			active_chains |= BIT(first_chain);
+			D_CALIB("All Tx chains are disconnected"
+				"- declare %d as connected\n", first_chain);
+			break;
+		}
+	}
+
+	if (active_chains != il->hw_params.valid_rx_ant &&
+	    active_chains != il->chain_noise_data.active_chains)
+		D_CALIB("Detected that not all antennas are connected! "
+			"Connected: %#x, valid: %#x.\n", active_chains,
+			il->hw_params.valid_rx_ant);
+
+	/* Save for use within RXON, TX, SCAN commands, etc. */
+	data->active_chains = active_chains;
+	D_CALIB("active_chains (bitwise) = 0x%x\n", active_chains);
+}
+
+static void
+il4965_gain_computation(struct il_priv *il, u32 * average_noise,
+			u16 min_average_noise_antenna_i, u32 min_average_noise,
+			u8 default_chain)
+{
+	int i, ret;
+	struct il_chain_noise_data *data = &il->chain_noise_data;
+
+	data->delta_gain_code[min_average_noise_antenna_i] = 0;
+
+	for (i = default_chain; i < NUM_RX_CHAINS; i++) {
+		s32 delta_g = 0;
+
+		if (!data->disconn_array[i] &&
+		    data->delta_gain_code[i] ==
+		    CHAIN_NOISE_DELTA_GAIN_INIT_VAL) {
+			delta_g = average_noise[i] - min_average_noise;
+			data->delta_gain_code[i] = (u8) ((delta_g * 10) / 15);
+			data->delta_gain_code[i] =
+			    min(data->delta_gain_code[i],
+				(u8) CHAIN_NOISE_MAX_DELTA_GAIN_CODE);
+
+			data->delta_gain_code[i] =
+			    (data->delta_gain_code[i] | (1 << 2));
+		} else {
+			data->delta_gain_code[i] = 0;
+		}
+	}
+	D_CALIB("delta_gain_codes: a %d b %d c %d\n", data->delta_gain_code[0],
+		data->delta_gain_code[1], data->delta_gain_code[2]);
+
+	/* Differential gain gets sent to uCode only once */
+	if (!data->radio_write) {
+		struct il_calib_diff_gain_cmd cmd;
+		data->radio_write = 1;
+
+		memset(&cmd, 0, sizeof(cmd));
+		cmd.hdr.op_code = IL_PHY_CALIBRATE_DIFF_GAIN_CMD;
+		cmd.diff_gain_a = data->delta_gain_code[0];
+		cmd.diff_gain_b = data->delta_gain_code[1];
+		cmd.diff_gain_c = data->delta_gain_code[2];
+		ret = il_send_cmd_pdu(il, C_PHY_CALIBRATION, sizeof(cmd), &cmd);
+		if (ret)
+			D_CALIB("fail sending cmd " "C_PHY_CALIBRATION\n");
+
+		/* TODO we might want recalculate
+		 * rx_chain in rxon cmd */
+
+		/* Mark so we run this algo only once! */
+		data->state = IL_CHAIN_NOISE_CALIBRATED;
+	}
+}
+
+/*
+ * Accumulate 16 beacons of signal and noise stats for each of
+ *   3 receivers/antennas/rx-chains, then figure out:
+ * 1)  Which antennas are connected.
+ * 2)  Differential rx gain settings to balance the 3 receivers.
+ */
+void
+il4965_chain_noise_calibration(struct il_priv *il, void *stat_resp)
+{
+	struct il_chain_noise_data *data = NULL;
+
+	u32 chain_noise_a;
+	u32 chain_noise_b;
+	u32 chain_noise_c;
+	u32 chain_sig_a;
+	u32 chain_sig_b;
+	u32 chain_sig_c;
+	u32 average_sig[NUM_RX_CHAINS] = { INITIALIZATION_VALUE };
+	u32 average_noise[NUM_RX_CHAINS] = { INITIALIZATION_VALUE };
+	u32 min_average_noise = MIN_AVERAGE_NOISE_MAX_VALUE;
+	u16 min_average_noise_antenna_i = INITIALIZATION_VALUE;
+	u16 i = 0;
+	u16 rxon_chnum = INITIALIZATION_VALUE;
+	u16 stat_chnum = INITIALIZATION_VALUE;
+	u8 rxon_band24;
+	u8 stat_band24;
+	unsigned long flags;
+	struct stats_rx_non_phy *rx_info;
+
+	if (il->disable_chain_noise_cal)
+		return;
+
+	data = &(il->chain_noise_data);
+
+	/*
+	 * Accumulate just the first "chain_noise_num_beacons" after
+	 * the first association, then we're done forever.
+	 */
+	if (data->state != IL_CHAIN_NOISE_ACCUMULATE) {
+		if (data->state == IL_CHAIN_NOISE_ALIVE)
+			D_CALIB("Wait for noise calib reset\n");
+		return;
+	}
+
+	spin_lock_irqsave(&il->lock, flags);
+
+	rx_info = &(((struct il_notif_stats *)stat_resp)->rx.general);
+
+	if (rx_info->interference_data_flag != INTERFERENCE_DATA_AVAILABLE) {
+		D_CALIB(" << Interference data unavailable\n");
+		spin_unlock_irqrestore(&il->lock, flags);
+		return;
+	}
+
+	rxon_band24 = !!(il->staging.flags & RXON_FLG_BAND_24G_MSK);
+	rxon_chnum = le16_to_cpu(il->staging.channel);
+
+	stat_band24 =
+	    !!(((struct il_notif_stats *)stat_resp)->
+	       flag & STATS_REPLY_FLG_BAND_24G_MSK);
+	stat_chnum =
+	    le32_to_cpu(((struct il_notif_stats *)stat_resp)->flag) >> 16;
+
+	/* Make sure we accumulate data for just the associated channel
+	 *   (even if scanning). */
+	if (rxon_chnum != stat_chnum || rxon_band24 != stat_band24) {
+		D_CALIB("Stats not from chan=%d, band24=%d\n", rxon_chnum,
+			rxon_band24);
+		spin_unlock_irqrestore(&il->lock, flags);
+		return;
+	}
+
+	/*
+	 *  Accumulate beacon stats values across
+	 * "chain_noise_num_beacons"
+	 */
+	chain_noise_a =
+	    le32_to_cpu(rx_info->beacon_silence_rssi_a) & IN_BAND_FILTER;
+	chain_noise_b =
+	    le32_to_cpu(rx_info->beacon_silence_rssi_b) & IN_BAND_FILTER;
+	chain_noise_c =
+	    le32_to_cpu(rx_info->beacon_silence_rssi_c) & IN_BAND_FILTER;
+
+	chain_sig_a = le32_to_cpu(rx_info->beacon_rssi_a) & IN_BAND_FILTER;
+	chain_sig_b = le32_to_cpu(rx_info->beacon_rssi_b) & IN_BAND_FILTER;
+	chain_sig_c = le32_to_cpu(rx_info->beacon_rssi_c) & IN_BAND_FILTER;
+
+	spin_unlock_irqrestore(&il->lock, flags);
+
+	data->beacon_count++;
+
+	data->chain_noise_a = (chain_noise_a + data->chain_noise_a);
+	data->chain_noise_b = (chain_noise_b + data->chain_noise_b);
+	data->chain_noise_c = (chain_noise_c + data->chain_noise_c);
+
+	data->chain_signal_a = (chain_sig_a + data->chain_signal_a);
+	data->chain_signal_b = (chain_sig_b + data->chain_signal_b);
+	data->chain_signal_c = (chain_sig_c + data->chain_signal_c);
+
+	D_CALIB("chan=%d, band24=%d, beacon=%d\n", rxon_chnum, rxon_band24,
+		data->beacon_count);
+	D_CALIB("chain_sig: a %d b %d c %d\n", chain_sig_a, chain_sig_b,
+		chain_sig_c);
+	D_CALIB("chain_noise: a %d b %d c %d\n", chain_noise_a, chain_noise_b,
+		chain_noise_c);
+
+	/* If this is the "chain_noise_num_beacons", determine:
+	 * 1)  Disconnected antennas (using signal strengths)
+	 * 2)  Differential gain (using silence noise) to balance receivers */
+	if (data->beacon_count != il->cfg->chain_noise_num_beacons)
+		return;
+
+	/* Analyze signal for disconnected antenna */
+	il4965_find_disconn_antenna(il, average_sig, data);
+
+	/* Analyze noise for rx balance */
+	average_noise[0] =
+	    data->chain_noise_a / il->cfg->chain_noise_num_beacons;
+	average_noise[1] =
+	    data->chain_noise_b / il->cfg->chain_noise_num_beacons;
+	average_noise[2] =
+	    data->chain_noise_c / il->cfg->chain_noise_num_beacons;
+
+	for (i = 0; i < NUM_RX_CHAINS; i++) {
+		if (!data->disconn_array[i] &&
+		    average_noise[i] <= min_average_noise) {
+			/* This means that chain i is active and has
+			 * lower noise values so far: */
+			min_average_noise = average_noise[i];
+			min_average_noise_antenna_i = i;
+		}
+	}
+
+	D_CALIB("average_noise: a %d b %d c %d\n", average_noise[0],
+		average_noise[1], average_noise[2]);
+
+	D_CALIB("min_average_noise = %d, antenna %d\n", min_average_noise,
+		min_average_noise_antenna_i);
+
+	il4965_gain_computation(il, average_noise, min_average_noise_antenna_i,
+				min_average_noise,
+				il4965_find_first_chain(il->cfg->valid_rx_ant));
+
+	/* Some power changes may have been made during the calibration.
+	 * Update and commit the RXON
+	 */
+	if (il->ops->update_chain_flags)
+		il->ops->update_chain_flags(il);
+
+	data->state = IL_CHAIN_NOISE_DONE;
+	il_power_update_mode(il, false);
+}
+
+void
+il4965_reset_run_time_calib(struct il_priv *il)
+{
+	int i;
+	memset(&(il->sensitivity_data), 0, sizeof(struct il_sensitivity_data));
+	memset(&(il->chain_noise_data), 0, sizeof(struct il_chain_noise_data));
+	for (i = 0; i < NUM_RX_CHAINS; i++)
+		il->chain_noise_data.delta_gain_code[i] =
+		    CHAIN_NOISE_DELTA_GAIN_INIT_VAL;
+
+	/* Ask for stats now, the uCode will send notification
+	 * periodically after association */
+	il_send_stats_request(il, CMD_ASYNC, true);
+}